<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>无标题文档</title>
<script>
window.onload=function ()
{
	var oTxt=document.getElementById('txt1');
	
	oTxt.onkeydown=function ()
	{
		return false;
	};
};
</script>
</head>

<body>
<input type="text" id="txt1" />
</body>
</html>
